Eucalyptus Silviculture.

 Eucalyptus Silviculture.

On 13th October 2021 I attended a course on the management of Eucalypts. There was a presentation at a hotel in the morning and a walk around the planted forestry of a former RFS president in the afternoon.

The majority of the 14 delegates were forestry consultants or managers, but I was pleased to see there were two other small non commercial woodlands represented. The morning session concentrated on the potential productivity of Eucalypts, in terms of dry matter biomass it easily exceeds other plants. Proper planting, aftercare, and thinning could all contribute to greater success. Most filing paper in the U.K. is from eucalyptus fibre from Portugal. The bad image that Portuguese Eucalypt plantations have is at least partly due to poor management. There is so much that that the local price can be low so stands are not thinned in a timely fashion. Lack of light causes lower leaf loss and the build up of a flammable layer. Low prices caused a similar neglect of British conifer plantations in the 80's and 90's and led to the poor state and the disease susceptibility of many conifer plantations in this centaury.  

9 year old Eucalyptus glaucescens, with 1 year old row thinning coppice.
 

Eucalypt timber and pulp are widely used in other parts of the world, it is ideal for plywood or CLT (cross laminated timber) but there are no English production plants and a huge amount of available material would be needed. Like so much of the U.K. forestry industry. There are not the economies of scale available elsewhere. For fuel wood and biomass it is by far the best, but a limited and low value market.

The estate we visited was in south Yorkshire on fairly light land. The preferred species was E. glaucescens  which does not do particularly well with me. It was confirmed that my woods are too wet for E.glaucescens. It is the most widely available Eucalypt it is less palatable and more frost hardy than the species I favour. It also photosynthesis  when the temperature is above 2C while dalyampleana, my go to Eucalypt,  stops at 5C.

E. delegatensis and E. dalrympeana
 from the same seed batch.

There are two photos of saplings, they can be seen to be totally different and from the same seed batch. I had always assumed that the odd different seedling in a seed batch was a hybrid. I seems that they can be different species and are due to incomplete cleaning of equipment at the seed company. The photo without the tube shows the yellow nature of the leaves that had formed within the tube. The speaker preferred mesh guards, the seedling duly fell over when the guard was removed but was held up by the time the photo was taken. 

It was comforting to find that many of the things I do are actually worth doing and I am not as mad as I sometimes seem.  The main learning point was that good silviculture is the same for almost all trees. The difference between Eucalypts and temperate trees is that light is the main determinant of the growth of  the later, while for Eucalypts  it is water availability, and they are very efficient at using it.  

Birch and coppice regeneration under 9 year old thinned Eualypts.

Eucalypt canopy leaves hang vertically to maximise light usage, so much more light reaches the ground, in the summer, than in other broadleaf woods.  

One of the reasons Eucalypts are not a wood of choice for carpentry is the are very hard when dry and blunt tools quickly. They are also too hard to take a nail. Something I need to test. The heart wood is fairly durable while the wide soft wood, which is visually indistinguishable is not, Something else to test.

In all a very instructive day.